Silverlight Unsaved Data Detection

using System;
using System.Collections.Generic;
using System.Text;
using System.Windows.Data;
using System.ComponentModel;
using System.Collections.ObjectModel;
using System.Windows.Input;
using System.Linq;
using System.Reflection;

namespace UnsavedDataDetection
{
    public class HomeViewModel : INotifyPropertyChanged
    {
        public HomeViewModel()
        {
            // Set the command property
            SaveCommand = new DelegateCommand(Save, CanSave);

            // Wire-up property changed event handler
            PropertyChanged += new PropertyChangedEventHandler(HomeViewModel_PropertyChanged);

            // Set default values
            FullName = "John Doe";
            Email = "JohnDoe@Whitehouse.gov";
        }

        // Commands

        #region SaveCommand
        public ICommand SaveCommand { get; set; }
        public void Save(object param)
        {
            // Clear IsDirty Flag 
            // (normally you would actually perform a save first)

            // Get an instance of the App class
            App AppObj = (App)App.Current;

            // Clear all the ISDirty flags
            AppObj.objApplicationState.ClearIsDirty();

            // Set IsDirty on this class
            IsDirty = false;
        }
        private bool CanSave(object param)
        {
            // Only enable if form is Dirty
            return (IsDirty);
        } 
        #endregion

        // Properties

        #region IsDirty
        private bool _IsDirty;
        public bool IsDirty
        {
            get { return _IsDirty; }
            set
            {
                if (IsDirty == value)
                {
                    return;
                }
                _IsDirty = value;
                this.NotifyPropertyChanged("IsDirty");
            }
        }
        #endregion

        #region FullName
        private string _FullName;
        public string FullName
        {
            get { return _FullName; }
            set
            {
                if (FullName == value)
                {
                    return;
                }
                _FullName = value;
                this.NotifyPropertyChanged("FullName");
            }
        }
        #endregion

        #region Email
        private string _Email;
        public string Email
        {
            get { return _Email; }
            set
            {
                if (Email == value)
                {
                    return;
                }
                _Email = value;
                this.NotifyPropertyChanged("Email");
            }
        }
        #endregion

        // Events

        #region HomeViewModel_PropertyChanged
        void HomeViewModel_PropertyChanged(object sender, PropertyChangedEventArgs e)
        {
            // Run this method for any property other than the IsDirty property
            // otherwise you will be in in infinate loop
            if (e.PropertyName != "IsDirty")
            {
                // Create a new ApplicationElement
                ApplicationElement objApplicationElement = new ApplicationElement();
                objApplicationElement.ElementKey = string.Format("HomeViewModel_{0}", e.PropertyName);
                objApplicationElement.ElementName = e.PropertyName;

                // Set ElementCurrentValue
                PropertyInfo pi = this.GetType().GetProperty(e.PropertyName);
                objApplicationElement.ElementCurrentValue = Convert.ToString(pi.GetValue(this, null));

                // Get an instance of the App class
                App AppObj = (App)App.Current;
                // Add the ApplicationElement to the objApplicationState object
                AppObj.objApplicationState.AddElement(objApplicationElement);

                // Set IsDirty
                IsDirty = (AppObj.objApplicationState.Elements.Where(x => x.IsDirty == true).Count() > 0);
            }
        }
        #endregion

        // Utility

        #region INotifyPropertyChanged
        public event PropertyChangedEventHandler PropertyChanged;

        private void NotifyPropertyChanged(String info)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(info));
            }
        }
        #endregion
    }
}